But let us return to _Kepler_. There is evidence that at various times in his life he wavered between his Lutheran confession and the Catholic faith, but that is as far as he went. He was of the opinion that the fundamental truths of both were in accord, and he would not presume to judge of the differences; he had taken a view-point of his own, from which he could not be made to recede. On the other hand, he was shocked when his fellow-Lutherans in Styria were on two occasions severely dealt with, although he personally had been treated with especial consideration. Otherwise his opinions on Catholic matters and the “wisdom” of the Catholic Church were eminently fair; he censured his co-religionists for their invidious attacks on Rome, and for their hesitancy in adopting the Gregorian reform of the calendar. He had friendly relation with many a Catholic scientist, was in correspondence with many Jesuits, was even frequently their guest, receiving stimulus, commendation, and scientific communications from them. To _Kepler_ the study of astronomy became largely a prayer; the finest of his scientific works he was wont to conclude with the doxology of the Psalmist, “Great is our Lord, and great is His power, and of His wisdom there is no number: praise Him ye Heavens; praise ye Him, O Sun, and Moon, ye Stars and light, and praise Him in your language. Thou, too, praise Him, O soul of mine, thy Lord, thy Creator, as long as it is granted to thee” (_Harmonices Mundi_, v. 9). His name and work is commemorated in the Keplerbund in Germany, which aims at the promotion of scientific knowledge in the sense of _Kepler_, in opposition to the misuse of natural science for purposes of materialism and atheism.